Improvement in construction of vessels



J. MACPHERSON.

Improvement in Construction of Vessels Patented June 25.1872.

Parana Qrrron JAMES MAOPHERSON, OF ABERDEEN, NORTH BRITAIN.-

lMPRC-VEMENT IN CONSTRUCTION OF VESS ELS.

Specification forming part of Letters Patent No. 128,407, dated June 25, 1872.

SPECIFICATION.

I, J mus MACPHERSON, of the city and county of Aberdeen, North Britain, engineer, have invented certain Improvements in the Construction of Steam and Sailing Ships, Yachts, and Boats, of which the following is a specification:

This invention relates to improvements in construction of ships or vessels propelled by steamthat is to say, either by a screw-propeller or paddle-wheels, or by the action of the wind upon the sails; but it may also be applied to yachts and boats. It is, however, more especially adapted for screw-propulsion, and consists in forming the hull with two keels extending its entire length, the keels converging together at the bow and diverging from each other at the stern. Thus a continuous hollow is produced between the two keels, into the stem end of which (in the case of ships, vessels, yachts, or boats being propelled by a screw-propeller) thescrew-propeller is placed, so that it rotates in the space between the two keels at that part where the said hollow or space is widest, and thus allows a propeller of greater diameter to be employed than can with facility be used in vessels as hitherto con structed.

The effect of this arrangement is that while increased steadiness is given to ships, vessels,

- yachts, or boats so arranged, the efficiency of the screw-propeller is increased by reason of the two keels confining the water set in motion between them, thus preventing the water from being scattered in an angular direction to so great an extent as obtains under existing arrangements of screw-propulsion. The opening between the keels at the bows, being narrower than toward the stern, prevents more water from entering the hollow than can find an easy course along the channel toward the stern, where the body of water is supplemented from below in order to give a full supply to the propeller, as at this point the discharge is always somewhat higher than the surrounding level. Each of the keels may be fitted with a rudder, and the rudders may be connected together by link-work so as to work conjointly, or they may be actuated separately or, in place of using twin rudders, a single rudder maybe employed. In the case of ships, vessels, yachts, or boats propelled by sails the construction is the same as that hereinbefore set forth, excepting that the screw-propeller is dispensed with, and an important result arising from constructing ships, vessels, yachts, or boats in the manner hereinbefore described is that greater steadiness of the ships, vessels, or yachts is thereby obtained, as well as fine water-lines, without an undue extension of length or the sacrifice of cargo capacity.

Another advantage accruing from this invention is that, in the case of ships, vessels, yachts, or boats propelled by screw-propellers, the propeller, being fully protected by the two keels, is kept safe from injury from loose float ing materials, dock-entrances, or walls, or the banks of canals, while, at the same time, in the .case of vessels constructed for canal navigation, the two keels prevent damage to the banks by confining between them the surge caused by the operation of the screw.

Description of Drawing.

On the sheet of drawing hereunto appended, Figure l is a longitudinal section of a ship or vessel represented as being propelled by means of a screw-propeller, A. Fig. 2 is an inverted plan thereof, or looking from the keels upward;

while Fig. 3 is an elevation of the stern-end of the same.

On these several figures the improvements which constitute this invention are illustrated; and they consist in constructing the hull of the ship or vessel with two keels, B B, extending throughout its entire length. The keels B B converge together toward the bows O of the ship or vessel, and diverge from each other toward its stem D, as more particularly seen in plan at Fig.2. Thus a continuous hollow space, E, is produced in the bottom of the ship or vessel between the two keels B B, and at the stern-end of this hollow space E the screwpropeller A is situated, as shown, so as to rotate between the two keels B B. By means of this arrangement increased steadiness in sailing is given to ships or vessels, and the efficiency of the screw A as a propeller is increased by the two keels B B confining between them the water set in motion by the action of the screw-propeller A, thereby preventing the water from being scattered in a direction angular to the vessels course to so great an extent as obtains under existing an rangements of ships or vessels propelled by screws. At the stern-end the keels B B are, or may be, tied together by means of a staybar, a, more particularly seen at Figs. 2 and 3, at the center of which another bar or post, 11, Figs. 1 and 2, is situated, the lower end of which is secured to the bar a, and its upper extremity to the overhanging portion of the stern of the ship or vessel, as shown at Fig. 1. The helm or rudder F is secured to the post I), and the pivot 00 at its lower extremity, on which it turns, rests on the stay-bar a, as shown at Figs. 1 and 3; or, in lieu of this arrangement, each keel may be furnished with a rudder or helm, as shown at F F on the stern-end elevation, Fig. 4, and by the diagram plan, Fig. 6-. Under the arrangement shown at Figs. 4 and 5, the rudders F at their upper ends are connected by links 0 c to opposite extremities of a lever, d, centered on a stud fixed to the deck of the vessel, as shown, by which means a parallel motion conjointly of the rudders is obtained; or the rudders F F may be actuated separately.

It is to be hereunderstood that the improvements constituting this invention are equally applicable to ships or vessels built of wood, iron, or a composition of both, and to yachts or boats, as well as to larger ships or vessels; andin the case of ships, vessels, yachts, or boats propelled by the action of the wind upon sails the construction is the same as that hereinbefore described and illustrated upon the appended sheet of drawing, excepting that the screw-propeller is dispensed with. The construction of ships, vessels, yachts, or boats is also the same in cases where propulsion by paddle-wheels is employed.

Claim.

A vessel, yacht, or boat having two keels diverging toward the stern, and between the said keels a channel, open at the bow, and 

